THEORY AND SIMULATION OF AN 85 GHZ QUASI-OPTICAL GYROKLYSTRON EXPERIMENT

The linear theory used to design a two-resonator 85 GHz quasioptical g yroklystron with a nonuniform magnetic field is presented. It is shown that a tapered magnetic field in the prebunching resonator has a rela tively small effect on the electron bunching parameter. The effect of velocity spread of the electron beam can be minimized by adjusting the magnetic field strength in the two resonators. Measured amplifier per formance is in good agreement with calculations from the nonlinear mul timode simulation code. Gyrophase bunching of the electrons is preserv ed over the long drift region (30 radiation wavelengths) even though n o attempt has been made to minimize the velocity spread of the beam.